A. Field of the Invention
The present invention relates to a mounting system for a wing mounted aircraft engine.
B. Brief Description of the Prior Art
In some aircraft designs, the engine or engines of the aircraft are mounted at the leading edge of the wing of the aircraft. The standard approach for mounting such an engine is to cantilever the engine from the front spar of the wing and design the front spar so that it has adequate strength to properly support the engine which extends forwardly therefrom.
An example of this is found in a type of STOL aircraft (i.e. short take-off and landing aircraft) utilizing "upper surface blowing", where the exhaust from the jet engine is directed over the upper surface of the wing. To obtain maximum benefit from this upper surface blowing, the exit nozzle of the engine should be located at a more forward cordwise location (e.g. at approximately the 20% point from the leading edge of the wing). This results in the engine's center of gravity being a considerable distance forward of the front spar to cause rather high moments being transmitted into the spar and other structure of the wing. Another factor which must be taken into consideration in supporting an engine from the wing is that the wing will generally be designed to flex along its length relative to the fuselage. Accordingly, the engine mounting arrangement should not interfere with the ability of the wing to flex, nor place any excessive loads on any of the aircraft components by reason of the wing flexing. It is to these problems that the present invention is directed.
A search of the prior art in the United States patents discloses a number of arrangement for mounting an engine to a wing and/or a fuselage of the aircraft. While none of the patents noted in the search relate directly to the considerations noted above, these patents are believed to be generally representative of various engine mounting arrangements of the prior art.
U.S. Pat. No. 1,796,765, Peterson, discloses an aircraft having a pair of engines mounted moderately below the wing of the aircraft. There are elongate struts connecting the engine to both the wing and the fuselage of the aircraft.
U.S. Pat. No. 1,816,129, Sikorsky, discloses an amphibian-type aircraft where a pair of engines are suspended from an aircraft wing. A plurality of struts form a framework which connects the the engine to the wing.
U.S. Pat. No. 2,076,393, Carden, discloses an aircraft which can function either as a glider (i.e. without power) or as a powered aircraft. An aircraft engine is hinge-mounted at a location above the fuselage. The engine is swung downwardly into a stowed position for gliding, and swung upwardly into the airstream above the aircraft when power from the engine is desired.
U.S. Pat. No. 2,398,704, Gassner, discloses an airplane having a pair of engines mounted at the leading edge of the wing with the nacelles supporting the two engines located beneath the wing. To resist vertical loads, a downwardly and inwardly extending strut is connected from the nacelle to the aircraft fuselage.
U.S. Pat. No. 2,815,184, Westphal et al, shows an aircraft where the engines are suspended from the underside of the body. A number of downwardly extending struts are provided to support the engine in that location.
U.S. Pat. No. 3,285,538, Burnelli, shows an aircraft having four engines mounted forwardly of the aircraft wing, these engines being arranged to discharge their jet exhaust over the upper surface of the wing. The patent states that the engines are supported directly from the body of the aircraft. However, the specific mounting arrangement is not disclosed in any detail.
British patent specification No. 762,785, Chaplin, discloses an aircraft engine connected by a pair of struts connected to both the fuselage and the wing of the aircraft.
French Pat. No. 1,328,994, discloses an aircraft having engines which are hinge-mounted so that the engines can be tilted to direct the exhaust of the engines in a more downward direction.